Toothbrush Head for Optimized Toothpaste Distribution

ABSTRACT

The present invention relates to a toothbrush head design with modified bristles for optimal toothpaste efficacy. The modified bristles are specifically designed to accommodate an optimal quantity of toothpaste and comprise a central reduction in the length of the bristles defining either a pea-shaped or rice-shaped cavity, depending on the age of the user. This particular design can be combined to any existing toothbrush and, more particularly, to toothbrush heads with various modified bristles. The present invention will improve toothpaste delivery to dental surfaces and, in particular, difficult-to-reach regions. The present invention provides, for the first time, a clear and simple guideline for health professionals as well as manufacturers for promoting optimal dosage.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present patent application claims the benefits of priority of commonly assigned American Provisional Patent Application No. 62/916,528, entitled “TOOTHBRUSH HEAD FOR OPTIMIZED TOOTHPASTE DISTRIBUTION” and filed at the American Patent Office on Oct. 17, 2019.

FIELD OF THE INVENTION

The present invention relates to toothbrushes, and relates more particularly to toothbrush heads with modified bristles in the center for optimal toothpaste application and a more efficient cleaning of teeth. The particular arrangement of bristles disclosed in the present invention can be applied to all types of toothbrushes and improves the effect of toothpaste on overall teeth and gum health in adults and, more particularly, eliminates and/or minimizes any adverse effects that chemicals, such as fluoride, found in toothpaste have on young children's health.

BACKGROUND OF THE INVENTION

Tooth decay is a multifactorial disease that is preventable through regular tooth brushing using toothpaste containing active agents [1]. Daily tooth brushing prevents gingivitis whereas active agents in toothpaste control carious lesions [2]. Following the mass-marketed and wide-spread introduction of fluoride in toothpaste in 1950s, the use of toothpaste was no longer for cosmetic purposes only but also had important therapeutic benefits [3]. This led to the adoption of fluoride toothpaste by over 500 million people worldwide [4] and is now considered the gold standard in the fight against caries.

Dental caries are the net result of consecutive cycles of de- and remineralization of dental tissues at the interface between the biofilm and the tooth surface [5]. Dental biofilm's composition is different in posterior versus anterior regions [6] which renders dental plaque less prevalent on anterior surfaces compared to posterior surfaces [7], in addition to caries hierarchy of attack being more severe on posterior teeth [8].

Brushing with fluoride toothpaste is a critical element in our defense against dental caries [9], however, optimal caries protection from the fluoride in toothpaste only happens when brushing delivers fluoride effectively [10]. In fact, the effectiveness of fluoride as a cariostatic agent depends on the availability of free fluoride in plaque during cariogenic challenge, i.e. during acid production. Thus, a constant supply of low levels of fluoride in biofilm/saliva/dental interference is considered the most beneficial in preventing dental caries [11]. Most of the active agents found in toothpaste for the control of caries work through a topical ions effect at the dental surface level [12], rendering the quantity of fluoride-containing toothpaste on the brush head a major health issue. Interestingly, in a comparative study of caries-prone versus caries-resistance individuals,

Sjogren et al. [13] found that the quantity of toothpaste applied on the brush head wasn't a predictor of fluoride concentrations within dental plaque or on overall caries experience. Although a longer brushing time would progressively reduce the retention of toothpaste within the toothbrush and therefore increase the amount delivered onto dental surfaces, people tend to have a short brushing time [14]. There appears to be a general consensus amongst oral healthcare professionals that individuals should spend at least 2 minutes brushing their teeth, twice a day. However, it is clear that the average time spent brushing by habitual toothbrush users is considerably shorter than 2 min, and a value of about 45 seconds seems like a more reasonable estimate [15].

In brief, oral healthcare professionals still face challenges such as fluoride ingestion, insufficient brushing time to optimize fluoride distribution and excessive toothpaste quantity applied on brush head. Different professional advices on these modern challenges are making users confused [16]. Although some methods of toothpaste application have been proposed, they have proven insufficient to lead to a desired level of prevention due to their reliance on patient/parent compliance [12]. Thus, the present invention will solve the need for a new toothbrush head design that takes into account all of these limitations.

Presently, toothpaste is applied on top of the bristles and, upon brushing, concentrates significantly at the initial brushing site, with only trace amounts reaching more distant regions. Most often, anterior regions are the initial sites although posterior regions are the regions that are most at risk. Moreover, young children chew the bristles, thereby ingesting significant and hazardous amounts of chemical ingredients found in toothpaste formulations. Finally, adults will tend to rinse frequently when reacting to the detergent taste of this large quantity of toothpaste, negating or diluting the expected effect.

Conventional toothbrushes generally consist of flat-trimmed, uniform length tufts of bristles, which are limited in their ability to conform to the curvature of teeth as well as penetrate the interproximal areas between the teeth. Several attempts have been made to modify bristle configuration with the hope of helping to reach problem areas that are difficult to reach with conventional toothbrushes. In addition to modifying bristle length and bristle arrangements to help reach the interproximal areas, newly improved mechanical bristle abrasion technologies have led to new variations in length, inclination and tufting patterns as well as different combinations of tapered and non-tapered bristles. These variations in bristle arrangements might very well increase the accessibility of the bristles into difficult-to-reach areas, however, they do not address one fundamental problem: how to standardize the optimal amount of toothpaste used every time? The present invention is adaptable to any toothbrush head with modified bristles. The specific bristle modification disclosed herewith can be combined to any existing toothbrush heads with modified bristles.

SUMMARY OF THE INVENTION

The present invention comprises a toothbrush head with center-modified bristles specifically designed to accommodate an optimal quantity of toothpaste. Furthermore, the toothbrush head with center-modified bristles has the advantage of guiding the user towards a standardized toothpaste aliquot. This has the advantage of reducing the risks associated with using excess toothpaste such as fluoride ingestion, especially in young children. The center-modified bristles form a pea-shaped cavity of approximately 2 mm deep and 3 mm long to accommodate an optimal and standardized amount of toothpaste every time. This particular design can be combined to any existing toothbrush and, more particularly, to toothbrush heads with various modified bristles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of the right-side of the TOOTHBRUSH HEAD according to the invention;

FIG. 2 is a left-side view of the TOOTHBRUSH HEAD of FIG. 1;

FIG. 3 is a right-side view of the TOOTHBRUSH HEAD of FIG. 1;

FIG. 4 is a front view of the TOOTHBRUSH HEAD of FIG. 1;

FIG. 5 is a rear view of the TOOTHBRUSH HEAD of FIG. 1;

FIG. 6 is a top view of the TOOTHBRUSH HEAD of FIG. 1;

FIG. 7 is a bottom view of the TOOTHBRUSH HEAD of FIG. 1; and

FIG. 8 is a cross-sectional view of the TOOTHBRUSH HEAD taken along line 8 of FIG. 4.

FIG. 9 depicts the spreading of toothpaste along dental surfaces with a conventional toothbrush on the left compared to the toothbrush head of the present invention on the right.

FIG. 10 shows an example of fluorosis and its detrimental effects on the appearance of tooth enamel.

FIG. 11 depicts toothpaste applied to pea-shaped versus rice-shaped cavity disclosed in different embodiments of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This invention consists of center-modified bristles 20 within a toothbrush head 10 which can be applied to all types of toothbrushes. The modification consists of a central reduction in the length of bristles 20 to define a pea-shaped cavity (approximately 2 mm deep×3 mm long) 30 as illustrated in FIGS. 1 to 8. This depression, or cavity, 30 in the bristles 20 allows the placement of the standardized required amount of toothpaste by the user or the caregiver. In the preferred embodiment of the present invention, parents will be able to apply the amount of pea-sized quantity of toothpaste, as is currently recommended [20]. For the prevention of tooth decay or of dentinal hypersensitivity, the toothpaste must be distributed to the maximum number of dental surfaces to respect the topical optimal effect. The present invention will optimize the dispersal of toothpaste along dental surfaces to improve dental caries prevention and dentinal hypersensitivity.

The present invention will solve a professional standardization problem by helping practitioners and parents make appropriate decisions concerning the use of fluoride as part of a comprehensive oral health care for infants, children, adolescents, and persons with special health care needs. [23] Optimal fluoride concentration in toothpaste for fighting caries is set at 1000 ppm [24] but this concentration is associated with dental fluorosis [25]. To avoid that chemical risk, recommendations suggest using concentration of 250 or 500 ppm [25] even though these are not effective amounts to prevent active carious lesions [26]. A longer brushing time progressively reduces retention of toothpaste within the bristles, thereby increasing the amount delivered to most dental surfaces. Although the general consensus amongst oral healthcare professional is that individuals should spend at least 2 minutes carefully brushing their teeth, twice a day, estimates of actual brushing time vary between just over 30 seconds to just over a minute [27] [28].

This less-than-optimal time spent brushing increases toothpaste retention within the bristles 20, thereby decreasing the fluoride amount delivered onto dental surfaces [28]. The present invention will compensate by keeping the majority of the toothpaste (i.e. fluoride) within the bristles 20 at the starting point and promote an even-spreading by allowing a gradual “exit” of the toothpaste from the bristles 20 towards the dental surfaces. Thus, the present invention will create, for the first time, a clear and simple guideline for manufacturers to promote optimal dosage.

In an alternative embodiment, the pea-shaped cavity 30 can be reduced to the size of a grain of rice for younger children. Many parents are squeezing potentially unhealthy amounts of toothpaste onto their children's toothbrushes [18]. Indeed, verbal instructions to limit the dose are ineffective and most parents use more fluoridated toothpaste than is recommended for young children. [21] There is still a lack of awareness of the proper guidelines regarding the selection and use of toothpastes in children [19]. In this alternative embodiment, the central reduction in the length of bristles 20 define a rice-shaped cavity (approximately 1 mm deep×2 mm long) 30. Studies have shown that the use of fluoride toothpaste before 6 years old was a risk indicator for fluorosis (FIG. 10) and, more importantly, brushing before the age of 2 years old with fluoride toothpaste increased the severity of fluorosis significantly [17]. Thus, the pea-shaped cavity 30 will accommodate an amount of toothpaste suitable for children older than 2 years old whereas the toothbrush head 10 having a rice-shaped cavity 30 will be suitable for children younger than 2 years old. The present invention will allow parents to easily control and limit the dose for her/his child and avoid irreversible dental fluorosis. [22]. In addition to these health hazards, this specially-designed cavity will prevent expensive toothpaste from going down the drain.

REFERENCES

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1. A toothbrush head, being connected to or connectable to a toothbrush grip handle, the toothbrush head comprising: a face and a longitudinal axis; and a plurality composed of a first and of a second type of tufts of bristles extending perpendicular to the face and each having a length; wherein: the first type of tufts of bristles is located close to the center of the face and to the longitudinal axis; the second type of tufts of bristles is located close to the perimeter of the face; and the tufts of bristles of the first type have shorter lengths than the lengths of the tufts of bristles of second type.
 2. The toothbrush head of claim 1, the tufts of bristles of the second type encircling the tufts of bristles of the first type.
 3. The toothbrush head of claim 1, the length of the tufts of bristles of the second type being of at least 1.0 cm.
 4. The toothbrush head of claim 1, the tufts of bristles of the first type defining a pea-shaped cavity within the tufts of bristles of the second type.
 5. The toothbrush head of claim 4, the cavity being from 1.5 to 2.5 mm deep compared to the length of the longest tuft of bristle of the second type and being from 2.0 to 4.0 mm long along the longitudinal axis.
 6. The toothbrush head of claim 1, the tufts of bristles of the first type defining a rice-shaped cavity within the tufts of bristles of the second type.
 7. The toothbrush head of claim 6, the cavity being about 1.0 mm deep from the length of the longest tuft of bristle of the second type and being about 2.0 mm long along the longitudinal axis.
 8. The toothbrush head of claim 1, the tufts of bristle of the first type defining a rectangular cavity within the tufts of bristles of the second type.
 9. The toothbrush head of claim 8, the cavity being from 1.5 to 2.5 mm deep compared to the length of the longest tuft of bristle of the second type and being from 2.0 to 4.0 mm long along the longitudinal axis.
 10. The toothbrush head of claim 8, the cavity being about 1.0 mm deep from the length of the longest tuft of bristle of the second type and being about 2.0 mm long along the longitudinal axis.
 11. The toothbrush head of claim 1, the toothbrush head comprising six tufts of bristles of the first type.
 12. A method for effectively dispersing toothpaste on teeth, the method comprising: applying toothpaste in a cavity of a toothbrush head, the cavity being made by extending tufts of bristles encircled by longer extending tufts of bristles; pressing the tufts of bristles comprising the toothpaste over teeth; and brushing for at least 30 seconds.
 13. The method of claim 12, the method further comprising: removing any applied toothpaste protruding out of the cavity prior to pressing the tufts of bristles over the teeth.
 14. The method of claim 12, the method further comprising: stopping the brushing when the fluoride concentration of the toothpaste over brushed teeth is between 250 to 500 ppm. 